YJIT: Fix raw sample stack lengths in exit traces #7728
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yjit-trace-exits appends a synthetic sample for the instruction being exited, but we didn't increment the size of the stack. Fixing this count correctly lets us successfully generate a flamegraph from the exits. I also replaced the line number for instructions with 0, as I don't think the previous value had meaning. Co-authored-by: Adam Hess <HParker@github.com>
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Sorry. Didn't spot this additional issue when doing #7702
yjit-trace-exits appends a synthetic sample for the instruction being exited, but we didn't increment the size of the stack. It wasn't clear where best to fix this, we did so here because it required the fewest changes.
I also replaced the line number for instructions with 0, as I don't think the previous value had meaning.
With this change we can successfully generate flamegraphs from exit locations.
With the stackprof default viewer
in speedscope (there's a hack in here because speedscope makes some poor assumptions so we need to pretend to be an object flamegraph. I hope to send a patch upstream)